Optimal timeframe for reporting short-term complication rates after total knee arthroplasty

This study attempts to identify the optimal follow-up period to report short-term complication rates after primary total knee arthroplasty. Discharge data from 1991 through 2001 was obtained from California and linked to state death records. Rates of mortality, infection, and pulmonary embolism were determined at 30-day intervals for up to 1 year postoperatively. An analysis of 222,684 primary total knee arthroplasties was performed. The peak rate and a large proportion of the complications that occurred during the first year after surgery were seen within the initial 30-day postoperative period. Regression analyses demonstrated that the patient and hospital characteristics predictive of outcome differed when comparing the results at 1 year postoperatively to shorter-term follow-up periods. The findings of this study indicate that 30- and 60-day follow-up periods provide an adequate accounting for adverse events related to mortality, infection, and pulmonary embolism. However, the regression results highlight the continued importance of reporting long-term outcomes.